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Nirmatrelvir/Ritonavir and Lurasidone Interaction

Drug interaction information between Nirmatrelvir/Ritonavir and Lurasidone.

Nirmatrelvir/Ritonavir and Lurasidone have a documented major interaction in FDA labeling.

FDA drug labeling documents a major-severity interaction between Nirmatrelvir/Ritonavir and Lurasidone. Major interactions are generally avoided, moderate ones may need monitoring or a dose adjustment, and minor ones are usually low-risk. This page shows the documented mechanism and guidance. Label-documented interactions are not a complete safety review, so always confirm your own medications with a pharmacist or doctor. Educational information, not medical advice.

Drug A

Nirmatrelvir/Ritonavir

Antiviral (Protease Inhibitor Combination)

Drug B

Lurasidone

Atypical Antipsychotic

How They Interact

Nirmatrelvir/ritonavir slows down the body's ability to clear lurasidone, causing it to build up to dangerous levels. This increase can lead to serious or life-threatening heart rhythm problems.

What To Do

This combination should be avoided because it is unsafe.

FDA Label Information

Antipsychotics lurasidone, pimozide ↑ lurasidone ↑ pimozide Co-administration contraindicated due to serious and/or life-threatening reactions such as cardiac arrhythmias [see Contraindications (4) ] .

Frequently Asked Questions

Can I take Nirmatrelvir/Ritonavir and Lurasidone together?

This is a major interaction. This combination should be avoided because it is unsafe.

How serious is the interaction between Nirmatrelvir/Ritonavir and Lurasidone?

This interaction is classified as "major" severity by the FDA. Major interactions may be life-threatening or cause serious side effects.

Why do Nirmatrelvir/Ritonavir and Lurasidone interact?

Nirmatrelvir/ritonavir slows down the body's ability to clear lurasidone, causing it to build up to dangerous levels. This increase can lead to serious or life-threatening heart rhythm problems.

Understanding the Nirmatrelvir/Ritonavir and Lurasidone Interaction

FDA-approved prescribing information for these two drugs flags their combination as a major-severity interaction. Nirmatrelvir/Ritonavir belongs to the Antiviral (Protease Inhibitor Combination) class and Lurasidone belongs to the Atypical Antipsychotic class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Nirmatrelvir/ritonavir slows down the body's ability to clear lurasidone, causing it to build up to dangerous levels. Severity tiers matter: major flags generally advise avoidance, moderate flags often require monitoring or dose adjustment, and minor flags may only call for awareness.

Context around a specific patient determines real-world impact. Nirmatrelvir/Ritonavir has 86 total documented interactions on file in this dataset, and Lurasidone has 15. Each additional medication compounds the interaction surface, which is why pharmacists run full-profile checks rather than evaluating one pair at a time. FDA-derived guidance for this pair is: This combination should be avoided because it is unsafe. Timing of doses, renal and hepatic function, age, and other concurrent prescriptions all shape whether a labeled interaction matters clinically.

An interaction flag is not a verdict. A large share of labeled interactions are managed routinely in clinical practice, the fix may be as simple as spacing doses or adding a monitoring test. Others require the prescriber to choose a different medication entirely. This page surfaces FDA-sourced labeling and openFDA data for educational purposes only; it is not medical advice and cannot account for your full clinical picture. Never start, stop, or adjust either Nirmatrelvir/Ritonavir or Lurasidone based on a web page, speak with your prescriber or pharmacist before making any change.

Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. Always consult your healthcare provider about drug interactions.